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In-vitro and in-vivo studies of the decrease of amphotericin B toxicity upon association with a triglyceride-rich emulsion.

L C Souza·R C Maranhão·S Schreier·A Campa
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Abstract

The effects of amphotericin B associated with a triglyceride-rich emulsion (AB-emulsion), shown previously to behave like lymph chylomicrons, were evaluated in vitro and in vivo. Incorporation of amphotericin B to the emulsion was monitored by UV-visible spectrophotometry. Whilst conventional amphotericin B induced a considerable K+ efflux from erythrocytes, AB-emulsion had essentially no effect. In contrast, the K+ efflux from Candida albicans was similar upon incubation either with AB-emulsion or with conventional amphotericin B. Administration to rats showed reduced mortality due to AB-emulsion compared with conventional amphotericin B. Renal toxicity was also decreased upon AB-emulsion treatment, as evaluated by serum urea and creatinine levels. These data suggest that chylomicron-like emulsions could be utilized as vehicles for amphotericin B in antifungal therapy.

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Amphotericin BAnimalsBody WeightCandida albicansDrug CarriersEmulsionsErythrocytesHumansKidney Function TestsLiver Function TestsMaleRatsRats, WistarTriglyceridesJournal ArticleResearch Support, Non-U.S. Gov't

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L C Souza, R C Maranhão, S Schreier, A Campa. 1993. In-vitro and in-vivo studies of the decrease of amphotericin B toxicity upon association with a triglyceride-rich emulsion.. https://doi.org/10.1093/jac%2F32.1.123

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Amphotericin B↗
PubMed2007

Correlation of Neo-Sensitabs tablet diffusion assay results on three different agar media with CLSI broth microdilution M27-A2 and disk diffusion M44-A results for testing susceptibilities of Candida spp. and Cryptococcus neoformans to amphotericin B, caspofungin, fluconazole, itraconazole, and voriconazole.

We compared the Neo-Sensitabs tablet assay to both reference M27-A2 broth microdilution and M44-A disk diffusion methods for testing susceptibilities of 110 isolates of Candida spp. and Cryptococcus neoformans to amphotericin B, caspofungin, fluconazole, itraconazole, and voriconazole. Neo-Sensitabs assay inhibition zone diameters in millimeters on three agars (Mueller-Hinton agar supplemented with 2% dextrose and 0.5 microg/ml methylene blue [MGM], Shadomy [SHA], and RPMI 1640 [RPMI, 2% dextrose]) were obtained at 24 to 72 h. The correlation coefficient of Neo-Sensitabs results with MICs was similar to that of the disk method for most of the five agents on MGM (R, 0.80 to 0.89 versus 0.76 to 0.89, respectively). Overall, superior correlation was observed at 24 h for most agents. The exception was amphotericin B (R values of 0.68 and 0.5 for disk and tablet, respectively, at 48 h versus 0.68 and 0.48, respectively, at 24 h). In general, Neo-Sensitabs results were less consistent on SHA and RPMI agars. Although agreement by breakpoint category of Neo-Sensitabs and disk results with CLSI method M27-A2 was also similar on MGM (92.7 to 98.2% versus 95.5 to 100%, respectively), the Neo-Sensitabs method failed to identify two of the six isolates with high amphotericin B MICs. These data suggest the potential value of the Neo-Sensitabs assay for testing at least four of the five agents against yeasts evaluated in the clinical laboratory.

Amphotericin B↗